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Goals

Regular use

Expected Results

Regular use

Actual Results

Firebase crashlytics reported the following iOS crash/exception coming from RealmJS. A crash happened when the app was started

crashlog from crashlytics:
Crashed: com.facebook.react.JavaScript
0 JavaScriptCore 0x1b164c548 bool JSC::symbolTableGet<JSC::JSGlobalObject>(JSC::JSGlobalObject*, JSC::PropertyName, JSC::PropertySlot&) + 88
1 JavaScriptCore 0x1b0e80f14 JSC::JSObject::get(JSC::JSGlobalObject*, JSC::PropertyName) const + 2516
2 JavaScriptCore 0x1b0e80f14 JSC::JSObject::get(JSC::JSGlobalObject*, JSC::PropertyName) const + 2516
3 JavaScriptCore 0x1b0e80490 JSObjectGetProperty + 144
4 PlusCards 0x104f13a6c realm::js::is_object_of_type(OpaqueJSContext const_, OpaqueJSValue const_, realm::js::String<realm::jsc::Types>) + 31 (jsc_value.hpp:31)
5 PlusCards 0x104f13998 realm::js::Value<realm::jsc::Types>::is_array(OpaqueJSContext const_, OpaqueJSValue const_ const&) + 63 (jsc_value.hpp:63)
6 PlusCards 0x104f5f258 realm::js::RealmClass<realm::jsc::Types>::create(OpaqueJSContext const_, OpaqueJSValue_, realm::js::Arguments<realm::jsc::Types>&, realm::js::ReturnValue<realm::jsc::Types>&) + 1028 (js_realm.hpp:1028)
7 PlusCards 0x104f59e84 OpaqueJSValue const* realm::js::wrap<&(realm::js::RealmClass<realm::jsc::Types>::create(OpaqueJSContext const_, OpaqueJSValue_, realm::js::Arguments<realm::jsc::Types>&, realm::js::ReturnValue<realm::jsc::Types>&))>(OpaqueJSContext const_, OpaqueJSValue_, OpaqueJSValue_, unsigned long, OpaqueJSValue const_ const_, OpaqueJSValue const_*) + 77 (jsc_return_value.hpp:77)
8 JavaScriptCore 0x1b0e6e85c long long JSC::APICallbackFunction::call<JSC::JSCallbackFunction>(JSC::JSGlobalObject_, JSC::CallFrame_) + 420
9 JavaScriptCore 0x1b0e238d8 llint_entry + 135240
10 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
11 JavaScriptCore 0x1b0e02648 vmEntryToJavaScript + 248
12 JavaScriptCore 0x1b13b1718 JSC::Interpreter::executeCall(JSC::JSGlobalObject_, JSC::JSObject_, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 444
13 JavaScriptCore 0x1b15971a8 JSC::profiledCall(JSC::JSGlobalObject*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 168
14 JavaScriptCore 0x1b0e834e0 JSObjectCallAsFunction + 504
15 PlusCards 0x104f5fdbc realm::js::RealmClass<realm::jsc::Types>::write(OpaqueJSContext const_, OpaqueJSValue_, realm::js::Arguments<realm::jsc::Types>&, realm::js::ReturnValue<realm::jsc::Types>&) + 30 (jsc_function.hpp:30)
16 PlusCards 0x104f5a04c OpaqueJSValue const* realm::js::wrap<&(realm::js::RealmClass<realm::jsc::Types>::write(OpaqueJSContext const_, OpaqueJSValue_, realm::js::Arguments<realm::jsc::Types>&, realm::js::ReturnValue<realm::jsc::Types>&))>(OpaqueJSContext const_, OpaqueJSValue_, OpaqueJSValue_, unsigned long, OpaqueJSValue const_ const_, OpaqueJSValue const_*) + 77 (jsc_return_value.hpp:77)
17 JavaScriptCore 0x1b0e6e85c long long JSC::APICallbackFunction::call<JSC::JSCallbackFunction>(JSC::JSGlobalObject_, JSC::CallFrame_) + 420
18 JavaScriptCore 0x1b0e238d8 llint_entry + 135240
19 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
20 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
21 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
22 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
23 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
24 JavaScriptCore 0x1b0e21010 llint_entry + 124800
25 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
26 JavaScriptCore 0x1b0e21010 llint_entry + 124800
27 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
28 JavaScriptCore 0x1b0e21010 llint_entry + 124800
29 JavaScriptCore 0x1b0e21010 llint_entry + 124800
30 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
31 JavaScriptCore 0x1b0e21f14 llint_entry + 128644
32 JavaScriptCore 0x1b0e21010 llint_entry + 124800
33 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
34 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
35 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
36 JavaScriptCore 0x1b0e21010 llint_entry + 124800
37 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
38 JavaScriptCore 0x1b0e22444 llint_entry + 129972
39 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
40 JavaScriptCore 0x1b0e21010 llint_entry + 124800
41 JavaScriptCore 0x1b0e20f68 llint_entry + 124632
42 JavaScriptCore 0x1b0e02648 vmEntryToJavaScript + 248
43 JavaScriptCore 0x1b13b1718 JSC::Interpreter::executeCall(JSC::JSGlobalObject_, JSC::JSObject_, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 444
44 JavaScriptCore 0x1b162ffc8 JSC::boundThisNoArgsFunctionCall(JSC::JSGlobalObject_, JSC::CallFrame_) + 712
45 JavaScriptCore 0x1b0e027c4 vmEntryToNative + 260
46 JavaScriptCore 0x1b13b176c JSC::Interpreter::executeCall(JSC::JSGlobalObject_, JSC::JSObject_, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 528
47 JavaScriptCore 0x1b15971a8 JSC::profiledCall(JSC::JSGlobalObject*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 168
48 JavaScriptCore 0x1b0e834e0 JSObjectCallAsFunction + 504
49 PlusCards 0x104ea2034 facebook::jsc::JSCRuntime::call(facebook::jsi::Function const&, facebook::jsi::Value const&, facebook::jsi::Value const*, unsigned long) + 1208 (JSCRuntime.cpp:1208)
50 PlusCards 0x104eaa3d8 facebook::jsi::Value facebook::jsi::Function::call<std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, facebook::jsi::Value>(facebook::jsi::Runtime&, std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, facebook::jsi::Value&&) const + 224 (jsi-inl.h:224)
51 PlusCards 0x104eaa238 std::*1::*function::*func<facebook::react::JSIExecutor::callFunction(std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, folly::dynamic const&)::$_4, std::*1::allocator<facebook::react::JSIExecutor::callFunction(std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, folly::dynamic const&)::$_4>, void ()>::operator()() + 217 (JSIExecutor.cpp:217)
52 PlusCards 0x104dd4b30 void std::*1::*invoke_void_return_wrapper<void>::*call<void (&)(std::*1::function<void ()> const&, std::*1::function<std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > ()>), std::*1::function<void ()> const&, std::*1::function<std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > ()> >(void (&)(std::*1::function<void ()> const&, std::*1::function<std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > ()>), std::*1::function<void ()> const&, std::*1::function<std::*1::basic_string<char, std::*1::char_traits<char>, std::__1::allocator<char> > ()>&&) + 1831 (functional:1831)
53 PlusCards 0x104ea8240 facebook::react::JSIExecutor::callFunction(std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, std::*1::basic_string<char, std::*1::char_traits<char>, std::*1::allocator<char> > const&, folly::dynamic const&) + 1831 (functional:1831)
54 PlusCards 0x104e9e678 std::*1::*function::*func<facebook::react::NativeToJsBridge::runOnExecutorQueue(std::*1::function<void (facebook::react::JSExecutor_)>)::$7, std::*1::allocator<facebook::react::NativeToJsBridge::runOnExecutorQueue(std::*1::function<void (facebook::react::JSExecutor)>)::$_7>, void ()>::operator()() + 1720 (functional:1720)
55 PlusCards 0x104df0750 facebook::react::tryAndReturnError(std::__1::function<void ()> const&) + 114464 (RCTCxxUtils.mm:114464)
56 PlusCards 0x104dfcf18 facebook::react::RCTMessageThread::tryFunc(std::__1::function<void ()> const&) + 59 (RCTMessageThread.mm:59)
57 CoreFoundation 0x1a1caf90c CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK

• 20
  58 CoreFoundation 0x1a1caf098 __CFRunLoopDoBlocks + 264
  59 CoreFoundation 0x1a1caa1d8 __CFRunLoopRun + 772
  60 CoreFoundation 0x1a1ca9ba8 CFRunLoopRunSpecific + 424
  61 PlusCards 0x104de6148 +[RCTCxxBridge runRunLoop] + 269 (RCTCxxBridge.mm:269)
  62 Foundation 0x1a2129e20 NSThread__start + 848
  63 libsystem_pthread.dylib 0x1a1a47d98 _pthread_start + 156
  64 libsystem_pthread.dylib 0x1a1a4b74c thread_start + 8
  1. Steps to Reproduce
     No idea. It happens sometime

Code Sample

–

Version of Realm and Tooling

• Realm JS SDK Version: 10.1.3
• Node or React Native: 0.62.2
• Client OS & Version: iOS 13.6.0, 13.5.1, 14.4.0
• Which debugger for React Native: None